Initially it is very difficult to find out internal fault in transformer. These internal faults are hazardous and causes overheating of transformer oil and winding, it consequences as insulation failure because of this uninterrupted power supply cannot be continued. It is more difficult to detect internal fault in small rating transformer. Buchholz Relay is classical method for detecting these internal faults in transformer but this method is based on generation of gasses during faults.
This work deals in a technique which is based on source formation of negative sequence current inside or outside of transformer for detecting internal fault. The protection against these fault with the help of differential relay connects both side of the transformer winding which compares the phase difference of negative sequence current.
[1]
Hadi Saadat,et al.
Power System Analysis
,
1998
.
[2]
김정호.
TRANSFORMER용 주요 자재
,
1999
.
[3]
D.G. Hart,et al.
Transformer Turn-to-Turn Fault Detection Using Hybrid Parameters
,
1992,
The 24th Southeastern Symposium on and The 3rd Annual Symposium on Communications, Signal Processing Expert Systems, and ASIC VLSI Design System Theory.
[4]
P. A. Crossley,et al.
Transformer protection based on the increment of flux linkages
,
2004
.
[5]
James S. Thorp,et al.
Power System Protection
,
2000
.
[6]
Pavlos S. Georgilakis,et al.
A Review of Transformer Losses
,
2009
.